Axial-flow turbine



F. LJUNGST-RM.

AXIAL FLOW TURBINE.

APPLlcATloN man APR.10,1919.

1,341,273. Patented May 25, 1920.

illlllmrlll l FREDRIK LJUNGSTBM, 0F BREVIK, LIDINGN, SWEDEN.

AXIAL-FLOW TURBINE.

Specilcation of Letters Patent.

Patented May 25, 1920.

Application led April 10, 1919. Serial No. 289,055.

To all whom 'it may concern Be it known that I, FREDRIK LJUNos'rRM,

subject of the King of Sweden, residing at Brevik, Lidingn, Sweden, have invented certain new and useful Improvement in Axial-Flow Turbines, of which the follow turbine on account of the very large dimenouter section to the discharge sions of the discharge conduits mostly used.

The presentA invention relates to an arrangement which allows of a shortening of the turbine by locating the discharge port of it radially outside of the parts of the turbine working at a higher pressure, z'. e. outside of the fixed casing carrying the uide blades and constituting the inner wall of the discharge port. V

The invention, furthermore, consists therein, that one"(or a few) of the last buckets of the'turbine is subdivided radially in two sections in such manner that the steam is first caused to flow, through the inner and then in the opposite direction through the outer section, the same at last 'escaping from this by the side thereof and inclosing the said casing.

An embodiment of the invention is shown by way of example in the accompanying drawing.

.Figure 1 is a vertical longitudinal sectional view of the improved turbine, and,

Fig. 2 isan enlarged sectional detail of a portion thereof.

The live steam enters the turbine through the opening l connected with the steam supply pipe, and flows through the passage 3 between the blades in the direction of the arrow 2. In this case only the last bucket 9 is extended with a bucket 4 located radially in a section 10 of the passage 3 outside ort located of the bucket 9, the said passage turning at 5 and leading the steam into the final outlet or discharge port 6. This outlet is in the present case located outside of the xed casinof 7 inclosing the parts of the turbine working with a higher pressure. 11 denotes the rotating blade-carrying drum which is attached to the turbine shaft 14C the same as the turbine disks 12 and 13.

To prevent leakage of steam from the passage 3 directly into the discharge port 6, the intermediate space between the rotating and the fixed parts is provided with a suitable packing. y'

As will be seen from the drawing, the steam passage between the inner and outer sections of the last buckets is formed so that the steam upon passing through the inner sections is compelled to turn so as to flow through the outer sections in the opposite direction, the buckets of the outer section being radially longer than the buckets of the inner section.

What I claim as new and desire to secure by Letters Patent of the United States is: An axial turbine wherein the last rotat ing blade section comprises two radially arranged concentric rings of blades an inner and outer so arranged that the steam first passes through the inner ring, a bent passage into which the steam passes after leaving the first ring of bladesand by which the steam is caused to flow in the opposite direction through the other ring, a discharge chamber into which the steam passes axi ally after leaving the last mentioned ring, and a housing withinl the chamber and surrounding the remaining blades.

In testimony whereof I affix my signature in presence of two witnesses.

FREDRIK LJ UNGSTRM.

Witnesses P. H. BERGRo'rH, GRETA PRIsH, 

